Artificial Surface
Gas giants like Jupiter cannot be terraformed in a classic way, because they have no solid surface. Still, in theory, it was proposed the construction of an artificial surface. There is also another alternative, the construction of flying islands that can support limited ecosystems and cities. The Concept The idea is that a planet-wide artificial surface or crust can be built above the atmosphere of a gas giant like Jupiter or Saturn. It will have an ellipsoidal shape. The crust needs to be strong enough to resist and not to collapse under its own weight. On top of it, Geographic features like oceans and continents can be built. There will be a breathable functional atmosphere above the surface and a structural atmosphere beneath it. The two layers of gas will be completely separated. The entire weight of the artificial crust will be counterbalanced by the pressure in the structural atmosphere. Major Challenges Even if this principle will work in theory, in practice, we don't know materials strong enough to resist. The artificial crust needs to hold its own weight. In addition, gas giants are known to have very powerful storms. Winds can reach over 1000 km/h and will stress the surface to incredible tensions. Jupiter, for example, has parallel bands, each one moving in opposite directions with high speeds. These forces are far stronger then magma currents that on Earth force plaque tectonics to move. Another problem is that, even if the surface is strong enough to resist, on a long timescale, winds from the structural atmosphere will slowly erode it with their continuous movement. Third, the crust needs to be elastic, to resist tidal forces from orbiting moons, from planet's sun and from other planets. As said above, there is no known material strong enough for building an artificial surface around a gas giant. But even if one day it will be discovered, we will need huge amounts of it. Encasing Jupiter with an artificial surface as thick as the Earth's crust will require a volume of material comparable in size with the planet Mars. The Result The newly created surface will have Geographic features that we want it to have. Climate simulation shows some interesting patterns (see Jupiter Simulation for details). First of all, Atmosphere Parameters are different from any other planet. Because of the high gravity and very high escape velocity, gas molecules will not be able to escape. The atmosphere of a terraformed Jupiter with this technology will only be a bit higher then 1 km, making difficult for air currents to circle around the planet. Also, given the large diameter, air currents will hardly mix temperatures between the equator and the poles. An Outer Planet tends to have a special type of climate known as Monoclime, with humidity rising to 100% and little to no temperature variations between equator and poles. This is the climate pattern one would expect to find on the moons of Jupiter (see Ganymede Simulation for example). For Jupiter, because air currents will hardly mix temperatures, at the equator will be hotter then on Earth's equator. Also, on Jupiter's poles it will be cooler then on Earth's poles. If the encased gas giant is in the Habitable Zone, then it will experience even higher temperature differences. At the equator it will be above 100 C, while at the poles it will be below -140 C. In such conditions, water will move to the poles, where it will condensate in huge glaciers. It is possible that even the atmosphere will condensate at the poles. Alternative View An alternative solution is the use of floating islands. They can be built on huge tanks filled with hydrogen or helium, floating in the vast atmospheres of gas giants. It is known that air currents of a gas giant move very fast. Still, they are not as dangerous as expected. Currents might exceed the speed of 1000 km/s, but still they move as a whole. The islands will move together with the currents, with the same great speed. It could be possible to sail in a current, by dropping a sail at various depths, to avoid entering places with strong turbulations. Atmosphere pressure increases fast with density change. So, a big floating island can have its hydrogen tanks at a few km depth, where pressure is far higher, while on top of it, pressure will be just fine for humans to live. Some gas giants have huge deposits of hydrogen and helium in their atmosphere. In such conditions, terraforming will be hard, because heavier gasses, like oxygen and nitrogen and Greenhouse Gases, will tend to go down, while lighter gasses will accumulate in the upper atmosphere. Still, if a gas giant can have its atmosphere terraformed, it will become an incredible and unique place. People, plants and animals will live on floating islands, separated by endless depths of air. See Also *Artificial Continents *Ground Insulation *Ocean Insulation Category:Technology